From 8d3e5b46083fe83210b683aec67e471a4a00225e Mon Sep 17 00:00:00 2001
From: SevenMonths <qinwen_shuai@163.com>
Date: Thu, 26 May 2022 13:09:05 +0800
Subject: [PATCH] =?UTF-8?q?=E6=B7=BB=E5=8A=A0(0232.=E7=94=A8=E6=A0=88?=
 =?UTF-8?q?=E5=AE=9E=E7=8E=B0=E9=98=9F=E5=88=97.md)=EF=BC=9APHP=E7=89=88?=
 =?UTF-8?q?=E6=9C=AC?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 problems/0232.用栈实现队列.md | 44 +++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/problems/0232.用栈实现队列.md b/problems/0232.用栈实现队列.md
index 1a56d9f3..6752651e 100644
--- a/problems/0232.用栈实现队列.md
+++ b/problems/0232.用栈实现队列.md
@@ -496,5 +496,49 @@ void myQueueFree(MyQueue* obj) {
 }
 ```
 
+PHP:
+```php
+// SplStack 类通过使用一个双向链表来提供栈的主要功能。[PHP 5 >= 5.3.0, PHP 7, PHP 8]
+// https://www.php.net/manual/zh/class.splstack.php
+class MyQueue {
+    // 双栈模拟队列：In栈存储数据；Out栈辅助处理
+    private $stackIn;
+    private $stackOut;
+    
+    function __construct() {
+        $this->stackIn = new SplStack();
+        $this->stackOut = new SplStack();
+    }
+
+    // In: 1 2 3  <= push  
+    function push($x) {
+        $this->stackIn->push($x);
+    }
+
+    function pop() {
+        $this->peek();
+        return $this->stackOut->pop();
+    }
+
+    function peek() {
+        if($this->stackOut->isEmpty()){
+            $this->shift();
+        }
+        return $this->stackOut->top();
+    }
+
+    function empty() {
+        return $this->stackOut->isEmpty() && $this->stackIn->isEmpty();
+    }
+
+    // 如果Out栈为空，把In栈数据压入Out栈
+    // In: 1 2 3 => pop    push => 1 2 3 :Out  
+    private function shift(){
+        while(!$this->stackIn->isEmpty()){
+            $this->stackOut->push($this->stackIn->pop());
+        }
+    }
+}
+```
 -----------------------
 <div align="center"><img src=https://code-thinking.cdn.bcebos.com/pics/01二维码一.jpg width=500> </img></div>